Electric switch



Sept. 15. 1925.

v 1,554,090 J. H. H EWITT ELECTRIC SWITCH Filed Dec. 29. 1924 PatentedSept. 15, 1925.

UNITED STATES JOHN HERBERT HEWITT, 0F BIRMINGHAM, ENGLAND.

ELECTRIC SWITCH.

Application filed. December 29, 1924. Serial No. 758,704.

To all whom it may concern:

Be it known that 1, JOHN HERBERT HEWITT, a subject of the King of GreatBritain, residing at Utility lVorks, Kenyon Street, Birmingham, in thecounty of lVarwick, England, have invented certain new and usefulImprovements in Electric Switches; and I do hereby declare the followingto be a full, clear, and exact description of the same.

This invention relates to electric switches and one of its objects is toprovide a switch particularly suitable for use in wireless work whereinthe mass of metal employed for the contacts and other switch parts isreduced to a minimum and wherein the metal parts are arranged to bewidely separated for reducing electrical capacity.

A further object of the present invention is to provide an improvedmethod of mounting the contact members whereby their insulation will bemore perfect than hitherto.

A further object of the present invention is to provide a generallyimproved construction of switch in which the manufacture of the variouscomponents can be carried out cheaply and quickly.

A further object of the present invention is to provide a switchparticularly suitable for wireless work wherein the operation of makingthe electrical connections is simplified.

Referring to the drawings Figure 1 is a side view partly in sectionshowing one form of switch constructed in accordance with my invention.

Figure 2 is a section on line 22 of Figure 1.

Figure 3 is a section on line 33 of Figure 2.

Figure 4 is an end view showing another form of switch constructed inaccordance with my invention.

Figure 5 is a section on line 55 of Figure 4:.

Figure 6 is a sectional plan upon an enlarged scale taken through theshank portion of one of the contacts.

In the construction illustrated in Figures 1 to 3 and in Figure 6, theswitch comprises an insulating base plate 1 having four sets ofstationary contacts. Each set of stationary contacts consists of twoouter contacts 2 and an inner contact 3.

Each contact is provided with a stem portion 4 of flat section andhaving tapering edges 5, which stem portion is driven into a hole 6which may be of circular form so that only the edges 5 of the metalforming the contact are in contact with the plate 1.

As seen from Figure 1, each of the contacts 2 or 3 is provided with apair of shoulders 7 which limit the motion of the contact through thehole 6.

Each contact is provided with a portion for engagement by the movablecontact, the said.

portion preferably being bent as shown at 8 both transversely andlongitudinally partially to embrace the material of the moving contactto be hereinafter described.

Those parts of the stationary contacts 2 and 3 which are to be engagedby the moving contacts are bent to V section so that when engaged by amoving contact formed of round section wire, two points of contact areobtained between the parts.

The inner contacts 3 are bent to the form shown clearly in Figure 2 andit will be seen that when the moving contact 9 engages any of thestationary contacts, it displaces same slightly so that the stationarycontact produces a spring re-action on the moving contact 9 and tends toretain it in any position into which it is moved. Further, the springpressure between the stationary and moving contacts produces andmaintains a firm electrical connection.

The switch is provided with a face plate 10 adapted to abut against theunderside of a panel. 11 and the plate 10 is provided with two endportions 12 which are secured to the base plate 1.

The face plate 10 is provided with an opening 13 and each of the endportions 12 is provided with a bearing 14.

In each of the bearings 14 is a screw 15 having its head 16 rotatablymounted in the bearing 14c.

The shanks of the screws 15 engage in a disc 17 having bosses 18 intowhich the screws engage.

The disc 17 receives a radial lever 19 which constitutes an operatinglever.

Each of the screws 15 receives an insulating block 20 mounted on one ofthe bosses 18 and engaged by the screws 15.

These blocks 20 are employed for carrying themoving contacts 9 eachofwhich may be made of wire as shown, bent into sector like form withthe ends2l engaging in holes in the insulating blocks 20.

A guide plate 22 having a closed ended slot 23 is provided through whichthe lever 19 extends, the guide plate 22 being preferably secured to theface plate 10 by screws such as 24:.

Each of the shankportions 4; of the stationary contacts 2 and 3constitutes aterminal and may be provided with a layer of solder whichcan be melted when required for forming-- the connections.

In the construction shown in Figures l and- 5, the switch has only asingle set of contacts. These contacts are constructed and arranged and"are in all respects identical with those already described and have beengiven the same reference numerals.

In this-case the face plate 26 is provided with only one end portion 27which is con nected to the base plate 28. The end portion 27- isprovided with a bearing 29 in which is located a rotatable pin 30associated with a disc 31 which receives the operating lever 19.

An insulating block 32 similar in purpose to the blocks 20 is attachedto the disc 31 by a screw 33.

The pin 30 is provided with a reduced end or shank 34 which is threadedand receives a nut 35 by which the pin is retained in position in thebearing 29.

The moving contact 9 is constructed and arranged in the same manner asthose described with reference to Figures 1, 2 and 3, as also is theguide plate 22.

hat I claimthen is 1. An electric switch comprising an insulating baseplate, a plurality of stationcontacts, each consisting of a thin resilient. strip of metal having a shank of flat section with taperededges forced through a hole in the base plate andcontacting said plateonly at said edges, each having portion bent partially to embrace amoving contact, a face plate disposed parallel tosaid base plate andhaving an opening, an end portion onsaid face plate connectingit' withsaid base plate, said end portion having a bearing, a metal pin mountedfor turning movement in saidbean ing, a lever arranged radially inrelation tosaid pin and associated therewith, said lever passing throughthe opening in the face plate, and constituting an operating lever, aninsulatingblock associated and moving with said pin, and a movingcontact of skeleton form mounted on said block and ra per-Ming withSaid, stationary contacts.

2. An electric switch comprising an insulting base plate, a plurality ofsets of stationary contacts arranged in rows on the base plate, eachcontact. consisting of a thin resilient strip of metal having a shank.forced. through. a hole in said base plate, and a portion for engagementby a moving contact, a face plate disposed parallel to said base plateand having an opening, two end, portions on said face plate connectingit to said base plate, each of said end portions having a bearing, apair of screws each having its head mounted for rotation in one of saidbearings, a metal disc having a boss. on each side into which saidscrews engage, a lever secured to and projecting radially from saiddisc, said lever passing through the opening in the face plate andconstituting an operating lever, an insulating block mounted upon eachof said bosses and secured by one of said screws, and sector-likemovingcontacts carried by said blocks and each co-operating with a set ofstationary contacts.

An electric switch comprising an insulating base plate, a plurality ofsets of stationary contacts arranged in rows on the base plate, eachcontact consisting of a thin resilient strip of metal having a shankforced through a hole in said base plate, and a portion for engagementby a moving contact, a face plate disposed parallel to said base plateand having an opening, two end portions on said face plate connecting itto said base plate each of said end portions having a bearing, a pair ofscrews each having its head mounted. for rotation in one of saidbearings, a metal disc having a boss on each side into which said screwsengage, a lever secured to and projecting radially from said disc, aguide plate disposed parallel with and in spaced relationship to said.face plate, "said guide plate having a closed ended slot, said leverpassing through said opening and said slotand constituting anoperating'levcr, an. insulating block mount-ed upon each of said bossesand secured by one of. said screws, and sector-like moving contactscarried by said blocks and each co-operating with a set of stationarycontacts.

4t. An electric switch comprisingan insulating base plate, a pluralityof station ary contacts, each consisting of a thin resilient strip ofmetal having a shank of flat section with tapered edges forced through ahole in the base plate an contacting said plate only at said edges, eachhaving a portion bent to V section partially to embrace a movingContact, a face plate disposed parallel to said base plate and having anopening, an end portion on said face plate connecting it with said baseplate, said end portion having a bearing, a metal pin mounted forturning movement in said bearing, a lever arranged radially in relationto said pin and associated therewith, said lever passing through theopening in the face plate and constituting an operating lever, aninsulating block associated and moving With said pin, and a movingcontact of skeleton form formed of round section Wire, mounted on saidblock and co-operating with said stationary contacts, whereby two pointsof 1 contact are obtained between the moving and stationary contacts.

In Witness whereof I aflix my signature.

JOHN HERBERT HEWITT.

